Integrated to Separates Advice

I currently have a Musical Fidelity KW500 integrated amp feeding a pair of JMLab/Focal Electra 1027be speakers. My primary purpose is ST music listening, but it is also part of a 5.1 theater.

The 5.1 theater is run by a middle-of-the-road Onkyo unit (nothing special, literally just something I needed in a hurry and it was readily available). It feeds out to the Musical Fidelity for the mains.

At the end of the day, I want to consolidate my Onkyo Receiver and my Musical Fidelity into a dedicated Pre-Amp/Amp combination. I don't want to have to worry about multiple pres or amps like I do now, however I don't want to take a massive hit in the SQ either.

I'm considering selling the Musical Fidelity KW500 and the Onkyo and replacing it with the Marantz AV8003 and MM8003 combo. However, given my current setup and listening (90% stereo music, 10% HT) would I be making a huge sacrifice? Will the MM8003 push the 1027be's sufficiently? If the Marantz equipment will be too large a hit in SQ, I'll deal with the inconvenience as SQ is ultimately more important, but I think I can deal with a marginal difference.

If anyone has heard these speakers on the Marantz setup, I would love to hear about it. Any other feedback or advice would be greatly appreciated.

Thanks!